This invention relates generally to means for terminating electrical conductors to multi-contact electrical connectors and more specifically to electrical connectors having a plurality of contact elements adapted to be terminated with pin contact members electrically secured to a plurality of insulated conductors. In particular, the present invention relates to an improved electrical connector termination system of the above type which utilizes an insulation-piercing pin/ribbon socket contact arrangement and improved means for releasably maintaining the electrical conductors and connector in a fully terminated condition.
The increasing practice, particularly in sophisticated electronics fields exemplified by the computer and telephone industries, to modularize and miniaturize electronic circuitry has brought on the problem of finding more efficient and reliable means for interconnecting and terminating individual circuit modules and cables containing plural insulated electrical conductors. Such interconnections should preferably be effected to facilitate rapid field termination and ready replacement or removal for servicing.
Recognizing these requirements, a wide variety of arrangements have been devised and employed to effect termination of plural insulation conductors with an electrical connector adapted to receive such conductors. In such multi-circuit electrical connectors, one common technique for terminating the individual conductors with the connector has been to strip the insulation from the end of the conductor and then solder the bare conductor end to a connector contact. This procedure requires considerable skill on the part of the workman making the solder connection, particularly in miniaturized connectors. There is also a tendency to bridge adjacent contacts of the connector during the soldering operation, producing undesired circuit connections.
Another widely utilized termination technique which has gained considerable acceptance entails the use of insulation-piercing terminals for the contact members of the connector. These terminals are adapted to cut through the insulation of the conductor and establish an electrical connection therewith without preliminary stripping and without the conventional soldering step. In multi-circuit electrical connectors, these insulation-piercing terminals frequently are in the form of ribbon contacts disposed within the connector housing.
In particular, U.S. Pat. No. 3,867,005, issued to Paul Hoppe, Jr., on Feb. 18, 1975, and U.S. Pat. No. 3,926,498, also issued to Paul Hoppe, Jr., on Dec. 16, 1975, both patents being assigned to the assignee of the present invention, disclose multi-circuit electrical connectors utilizing such insulation-piercing ribbon contact elements, the disclosures of which are specifically incorporated herein by reference. Referring to these patents, the insulated electrical conductors are securely terminated in a connector by forcibly inserting the insulated conductors transversely into longitudinally open channel-shaped contact elements disposed in the connector housing. These contact elements contain insulation-piercing notches whereby the notches penetrate the insulation and make electrical contact with the conductors. Furthermore, strain relief channels are provided in the connector housing at the open end of each contact element which, along with the insulation-piercing notches, aid in maintaining the termination connection between the insulated conductors and the connector.
While such connector termination systems are quite adequate for many purposes, there are certain instances whereby the transverse insertion of the insulated conductors into the connector's contact elements is either impossible or at least difficult. For example, in instances where such connectors are stacked in a row, as in telephone call box applications, termination by transverse insertion of the insulated conductors into the insulation-piercing elements of the electrical contacts is virtually impossible once the connectors have been stacked. Furthermore, large insertion tools are generally utilized for making such transverse connections, and this use of large tools in the field is difficult and cumbersome. Without the use of such specialized termination tools, however, transverse insertion of the conductors into the insulation-piercing contacts must be done by hand, one at a time, and this alternate method of connection is tedious as well as time consuming. Finally, it has been found that intermittency in operation sometimes occurs in connectors utilizing such insulation-piercing contacts when the terminated connectors have been subjected to severe vibration or rough handling.